1. Field of the Invention
The present invention relates to a control circuit for controlling a solid-state image pickup device, and to a method for driving an image pickup device. The control circuit for controlling a solid-state image pickup device according to the present invention specifically pertains to the technique of controlling the generation of timing signals for reading out, e.g. image data with a wide dynamic range. The method for driving an image pickup device according to the present invention pertains especially to a procedure of reading out signal charges from a solid-state image pickup device which provides for a wide dynamic range.
2. Description of the Background Art
U.S. Patent Application Publication 2003/0141564 A1 to Ryuji Kondo, et al., teaches a solid-state image pick up device in which two pixels, or photosensitive cells, of different photo-sensitivities are employed for each pixel in order to provide for a wide dynamic range. Each pixel is divided into two photosensitive areas, one formed to a higher sensitivity and the other formed to a lower sensitivity, in order to output pixel data of higher and lower sensitivities free of spatial deviation or deviation along time axis. Two images with different sensitivities may be obtained simultaneously by outputting these two sorts of pixel data as one pixel.
If a plural number of color filter segments, arranged on opposite sides of a vertical transfer path, are taken into consideration, color filter segments are arranged in a column of green segments G and a column of blue segments B and red segments R on one side of the vertical transfer path, and a column of green segments G and a column of red segments R and blue segments B on the other side of the vertical transfer path. The pixels are read with the set of the column of green segments G and the column of blue segments B and red segments R in one field and with the set of the column of green segments G and the column of red segments R and blue segments B in the other field.
Meanwhile, interlace readout of signal charges from such an image pickup device does not cause the pixel data of high and low sensitivities to be output separately from each other. Thus, for readout, a line memory is needed for temporarily storing the two sorts of the pixel data, and hence the use of such a solid-state image pickup device leads to increased costs.